When will we have use for these "Reputation Points"?

I'm fine with keeping them soley as an indicator that I'm contibuting in a positive way to the community.

I also use it to decide on how much effort I'll put into discussions with other users. If a user I'm talking with has a consistently low or negative reputation then they are more likely a troll or combatative person who is really not worth wasting your time in engaging with in detail.